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31.
This paper discusses the general methodological controversy between individual and group research approaches by comparing the main characteristics of these two methods as applied to the specific context of basic research on voluntary heart rate control. A review of the literature published over the past 19 years in this area of study shows an imbalance in the frequency of utilization of these two methods that strongly favors short-term group designs. Implications of this research tendency are discussed. The relevance and the advantages of applying the individual approach to voluntary autonomic control research are outlined. This area is particularly amenable to the individual approach because the phenomena under study seem to be characterized by, among other things, a smaller intrasubject than intersubject variability. It is suggested that the present imbalanced tendency in the choice of a research method be corrected and that researchers adopt a more flexible attitude in the choice of the best method for studying each specific problem.  相似文献   
32.
A complete neurobiological understanding of speech motor control requires determination of the relationship between simultaneously recorded neural activity and the kinematics of the lips, jaw, tongue, and larynx. Many speech articulators are internal to the vocal tract, and therefore simultaneously tracking the kinematics of all articulators is nontrivial—especially in the context of human electrophysiology recordings. Here, we describe a noninvasive, multi-modal imaging system to monitor vocal tract kinematics, demonstrate this system in six speakers during production of nine American English vowels, and provide new analysis of such data. Classification and regression analysis revealed considerable variability in the articulator-to-acoustic relationship across speakers. Non-negative matrix factorization extracted basis sets capturing vocal tract shapes allowing for higher vowel classification accuracy than traditional methods. Statistical speech synthesis generated speech from vocal tract measurements, and we demonstrate perceptual identification. We demonstrate the capacity to predict lip kinematics from ventral sensorimotor cortical activity. These results demonstrate a multi-modal system to non-invasively monitor articulator kinematics during speech production, describe novel analytic methods for relating kinematic data to speech acoustics, and provide the first decoding of speech kinematics from electrocorticography. These advances will be critical for understanding the cortical basis of speech production and the creation of vocal prosthetics.  相似文献   
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CLASEY, JODY L, CLAUDE BOUCHARD, LAURIE WIDEMAN, JILL KANALEY, C DAVID TEATES, MICHAEL O THORNER, MARK L HARTMAN, ARTHUR WELTMAN. The influence of anatomical boundaries, age, and sex on the assessment of abdominal visceral fat. Single-slice abdominal computed tomography (CT) scanning has been used extensively for the measurement of abdominal visceral fat (AYF). Optimal anatomical scan location and pixel density ranges have been proposed and are specifically reported to allow for the replication and standardization of AVF measurements. Standardization of the anatomical boundaries for CT measurement of AVF and the influence of age and gender on results obtained with different boundary locations have received much less attention. To determine the influence of three boundary analysis methods (AVF-1, AVF-2, and AVF-3) on the measurement of AVF by CT, 54 older (60 years to 79 years) and 37 younger (20 years to 29 years) healthy men and women were examined. The measurement boundary for AVF-1 was the internal most aspect of the abdominal and oblique muscle walls, and the posterior aspect of the vertebral body. AVF-2 used fat measurements enclosed in a boundary formed by the midpoint of the abdominal and oblique muscle walls, and the most posterior aspect of the spinous process. AVF-3 used fat measurements enclosed in a boundary formed by the external border of the abdominal and oblique muscle walls, and the external border of the erector spinae. Greater AVF measures were obtained with AVF-2 and AVF-3 compared with AVF-1 (p<0.0001). These differences were greater in older compared with younger subjects (p<0.0001) and greater in women compared with men (p<0.02). The significantly greater AVF measurements obtained with AVF-2 and AVF-3 resulted from the inclusion of larger amounts of fat that are not drained by the portal circulation. This included retroperitoneal, intermuscular, and intramuscular lipid droplets, which increase with aging. On the basis of these results, we recommend the AVF-1 anatomical boundaries for the measurement of AVF in clinical investigations, particularly with older subjects. These data demonstrate the importance of precise and reproducible anatomical boundaries for the measurement of AVF, particularly in longitudinal studies.  相似文献   
35.
Climate change is altering phenology; however, the magnitude of this change varies among taxa. Compared with phenological mismatch between plants and herbivores, synchronization due to climate has been less explored, despite its potential implications for trophic interactions. The earlier budburst induced by defoliation is a phenological strategy for plants against herbivores. Here, we tested whether warming can counteract defoliation‐induced mismatch by increasing herbivore‐plant phenological synchrony. We compared the larval phenology of spruce budworm and budburst in balsam fir, black spruce, and white spruce saplings subjected to defoliation in a controlled environment at temperatures of 12, 17, and 22°C. Budburst in defoliated saplings occurred 6–24 days earlier than in the controls, thus mismatching needle development from larval feeding. This mismatch decreased to only 3–7 days, however, when temperatures warmed by 5 and 10°C, leading to a resynchronization of the host with spruce budworm larvae. The increasing synchrony under warming counteracts the defoliation‐induced mismatch, disrupting trophic interactions and energy flow between forest ecosystem and insect populations. Our results suggest that the predicted warming may improve food quality and provide better growth conditions for larval development, thus promoting longer or more intense insect outbreaks in the future.  相似文献   
36.
All genus-group names listed in the second edition of the catalogue (1833-1836) of Dejean’s beetle collection are recorded. For each new genus-group name the originally included available species are listed and for generic names with at least one available species, the type species and the current status are given. Names available prior to the publication of Dejean’s second catalogue (1833-1836) are listed in an appendix.The following new synonymies are proposed: Cyclonotum Dejean, 1833 (= Dactylosternum Wollaston, 1854) [Hydrophilidae], Hyporhiza Dejean, 1833 (= Rhinaspis Perty, 1830) [Scarabaeidae], Aethales Dejean, 1834 (= Epitragus Latreille, 1802) [Tenebrionidae], Arctylus Dejean, 1834 (= Praocis Eschscholtz, 1829) [Tenebrionidae], Euphron Dejean, 1834 (= Derosphaerus Thomson, 1858) [Tenebrionidae], Hipomelus Dejean, 1834 (= Trachynotus Latreille, 1828) [Tenebrionidae], Pezodontus Dejean, 1834 (= Odontopezus Alluaud, 1889) [Tenebrionidae], Zygocera Dejean, 1835 (= Disternopsis Breuning, 1939) [Cerambycidae], and Physonota Chevrolat, 1836 (= Anacassis Spaeth, 1913) [Chrysomelidae]. Heterogaster pilicornis Dejean, 1835 [Cerambycidae] and Labidomera trimaculata Chevrolat, 1836 [Chrysomelidae] are placed for the first time in synonymy with Anisogaster flavicans Deyrolle, 1862 and Chrysomela clivicollis Kirby, 1837 respectively. Type species of the following genus-group taxa are proposed: Sphaeromorphus Dejean, 1833 (Sphaeromorphus humeralis Erichson, 1843) [Scarabaeidae], Adelphus Dejean, 1834 (Helops marginatus Fabricius, 1792) [Tenebrionidae], Cyrtoderes Dejean, 1834 (Tenebrio cristatus DeGeer, 1778) [Tenebrionidae], Selenepistoma Dejean, 1834 (Opatrum acutum Wiedemann, 1823) [Tenebrionidae], Charactus Dejean, 1833 (Lycus limbatus Fabricius, 1801) [Lycidae], Corynomalus Chevrolat, 1836 (Eumorphus limbatus Olivier, 1808) [Endomychidae], Hebecerus Dejean, 1835 (Acanthocinus marginicollis Boisduval, 1835) [Cerambycidae], Pterostenus Dejean, 1835 (Cerambyx abbreviatus Fabricius, 1801) [Cerambycidae], Psalicerus Dejean, 1833 (Lucanus femoratus Fabricius, 1775) [Lucanidae], and Pygolampis Dejean, 1833 (Lampyris glauca Olivier, 1790) [Lampyridae]. A new name, Neoeutrapela Bousquet and Bouchard [Tenebrionidae], is proposed for Eutrapela Dejean, 1834 (junior homonym of Eutrapela Hübner, 1809).The following generic names, made available in Dejean’s catalogue, were found to be older than currently accepted valid names: Catoxantha Dejean, 1833 over Catoxantha Solier, 1833 [Buprestidae], Pristiptera Dejean, 1833 over Pelecopselaphus Solier, 1833 [Buprestidae], Charactus Dejean, 1833 over Calopteron Laporte, 1836 [Lycidae], Cyclonotum Dejean, 1833 over Dactylosternum Wollaston, 1854 [Hydrophilidae], Ancylonycha Dejean, 1833 over Holotrichia Hope, 1837 [Scarabaeidae], Aulacium Dejean, 1833 over Mentophilus Laporte, 1840 [Scarabaeidae], Sciuropus Dejean, 1833 over Ancistrosoma Curtis, 1835 [Scarabaeidae], Sphaeromorphus Dejean, 1833 over Ceratocanthus White, 1842 [Scarabaeidae], Psalicerus Dejean, 1833 over Leptinopterus Hope, 1838 [Lucanidae], Adelphus Dejean, 1834 over Praeugena Laporte, 1840 [Tenebrionidae], Amatodes Dejean, 1834 over Oncosoma Westwood, 1843 [Tenebrionidae], Cyrtoderes Dejean, 1834 over Phligra Laporte, 1840 [Tenebrionidae], Euphron Dejean, 1834 over Derosphaerus Thomson, 1858 [Tenebrionidae], Pezodontus Dejean, 1834 over Odontopezus Alluaud, 1889 [Tenebrionidae], Anoplosthaeta Dejean, 1835 over Prosopocera Blanchard, 1845 [Cerambycidae], Closteromerus Dejean, 1835 over Hylomela Gahan, 1904 [Cerambycidae], Hebecerus Dejean, 1835 over Ancita Thomson, 1864 [Cerambycidae], Mastigocera Dejean, 1835over Mallonia Thomson, 1857 [Cerambycidae], Zygocera Dejean, 1835 over Disternopsis Breuning, 1939 [Cerambycidae], Australica Chevrolat, 1836 over Calomela Hope, 1840 [Chrysomelidae], Edusa Chevrolat, 1836 over Edusella Chapuis, 1874 [Chrysomelidae], Litosonycha Chevrolat, 1836 over Asphaera Duponchel and Chevrolat, 1842 [Chrysomelidae], and Pleuraulaca Chevrolat, 1836 over Iphimeis Baly, 1864 [Chrysomelidae]. In each of these cases, Reversal of Precedence (ICZN 1999: 23.9) or an applicationto the International Commission on Zoological Nomenclature will be necessary to retain usage of the younger synonyms.  相似文献   
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Offspring exposed to gestational diabetes mellitus (GDM) have an increased risk for chronic diseases, and one promising mechanism for fetal metabolic programming is epigenetics. Therefore, we postulated that GDM exposure impacts the offspring’s methylome and used an epigenomic approach to explore this hypothesis. Placenta and cord blood samples were obtained from 44 newborns, including 30 exposed to GDM. Women were recruited at first trimester of pregnancy and followed until delivery. GDM was assessed after a 75-g oral glucose tolerance test at 24–28 weeks of pregnancy. DNA methylation was measured at > 485,000 CpG sites (Infinium HumanMethylation450 BeadChips). Ingenuity Pathway Analysis was conducted to identify metabolic pathways epigenetically affected by GDM. Our results showed that 3,271 and 3,758 genes in placenta and cord blood, respectively, were potentially differentially methylated between samples exposed or not to GDM (p-values down to 1 × 10−06; none reached the genome-wide significance levels), with more than 25% (n = 1,029) being common to both tissues. Mean DNA methylation differences between groups were 5.7 ± 3.2% and 3.4 ± 1.9% for placenta and cord blood, respectively. These genes were likely involved in the metabolic diseases pathway (up to 115 genes (11%), p-values for pathways = 1.9 × 10−13 < p < 4.0 × 10−03; including diabetes mellitus p = 4.3 × 10−11). Among the differentially methylated genes, 326 in placenta and 117 in cord blood were also associated with newborn weight. Our results therefore suggest that GDM has epigenetic effects on genes preferentially involved in the metabolic diseases pathway, with consequences on fetal growth and development, and provide supportive evidence that DNA methylation is involved in fetal metabolic programming.  相似文献   
39.
The endosomal LeNHX2 ion transporter exchanges H+ with K+ and, to lesser extent, Na+. Here, we investigated the response to NaCl supply and K+ deprivation in transgenic tomato (Solanum lycopersicum L.) overexpressing LeNHX2 and show that transformed tomato plants grew better in saline conditions than untransformed controls, whereas in the absence of K+ the opposite was found. Analysis of mineral composition showed a higher K+ content in roots, shoots and xylem sap of transgenic plants and no differences in Na+ content between transgenic and untransformed plants grown either in the presence or the absence of 120 mm NaCl. Transgenic plants showed higher Na+/H+ and, above all, K+/H+ transport activity in root intracellular membrane vesicles. Under K+ limiting conditions, transgenic plants enhanced root expression of the high‐affinity K+ uptake system HAK5 compared to untransformed controls. Furthermore, tomato overexpressing LeNHX2 showed twofold higher K+ depletion rates and half cytosolic K+ activity than untransformed controls. Under NaCl stress, transgenic plants showed higher uptake velocity for K+ and lower cytosolic K+ activity than untransformed plants. These results indicate the fundamental role of K+ homeostasis in the better performance of LeNHX2 overexpressing tomato under NaCl stress.  相似文献   
40.
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